regular paper costs $3.79 per ream
recycled paper costs $5.49 per ream
$582.44 was spent for 116 reams
the numbers of reams of each type that were purchased
Let r and g represent the numbers of reams of regular and recycled ("green") paper, respectively.
... r + g = 116 . . . . . . . . 116 reams were purchased
... 3.79r + 5.49g = 582.44 . . . . this is the total cost of the purchase
Solve the first equation for r and substitute that into the second equation.
... r = 116 - g
... 3.79(116 - g) + 5.49g = 582.44 . . . . . use the expression for r
... 1.70g + 439.64 = 582.44 . . . . . . . . . simplify
... g = (582.44 -439.64)/1.70 = 84 . . . . subtract the constant, divide by 1.70
... r = 116 -84 = 32 . . . . . . . . . . . . . . . . . use the equation for r
32 regular reams and 84 recycled reams were purchased